Chantry Flats - before 6am?

Cycled up Chantry Flats for the first time today — it was great but I worry that on a less misty & rainy day the cars would make it dangerous.

Is it possible to hop on the road before it opens at 6am to ride up without traffic in peace, say at 530am?

Always looking for others with the same tastes to join me :—)